The Dallas daily herald. [volume] (Dallas, Tex.) 1873-1887, 1887-11-22
BEAVERS AS CONSTRUCTORS.
How They Build Dams-Thcir
Ability 20 REMAIN Under Water.

LHc lOVht0 0soVe' Noe"i"ioso h"'S
often spoken in admiration Of the con-
structive ability Of the beaver. Indeed,
it is one of the things that staggers
Darwin in the belief of his own theory.
But there is another thing l think
more wonderful still; that is the I'M
erring skill they possess to choose the
best places to build their dams. No
engineer, fully acquainted with all
their needs, could lay out q moro suit
able place than they themselves will do.
This is the more astonishing to those
who are well acquainted with their
nature, and know the fact that they
are not, as writers often represent
them to be, the most intelligent Of
animals, but on the contrary, possess
less general intelligence than the most
of brutes. If creek has branch run
ming into it, and If below the junction
of the two streams, the high lands come
within reasonable distance Of each
other, the beavers are sure to dam
such place. And if the high lands
widen out above. and the valley is
level. so as to form long, wide flats up
the two streams, the dam will be
large one. for next to a lake. it Is the
favoritc locality for them.
And now word about their dam
building. Their skill at this would put
to blush many of the professional dam
builders who went about erecting the
water-mills OF earlier times. and can
not be excelled by man after the great
est experience. If they intend to raise
the water only few feet they build on
the place as they find it, trusting to
their skill in pudding Qor they are the
best of puddlers) to stop any leak that
may occur But If they wish to raise a
high dam, such as probably will be
found in place like | am writing
about they will clear away all the rub
Dish and loose earth. leaving n clean
foundation for their work. Having
cleaned out the channel, they at first
haul in poles and large pieces of brush,
LAYING the large or butt ends down the
stream, and as they raise the pile. draw
ing it in so as TO form an apron below
for the water to fall on. and thus pre-
vent it from undermining the dam, fur
nishing the upper part with finer ma
terial than they have used below. After
a sufliciency of this material is placed
in position, they fill it with earth, which
they carry rolled into balls in their fore
arms pressed against their breasts, and
make the dam before they leave it al
most bottle tight They are not so par
ticular about the wings Of the dam run
ming from the channel of the creek over
the flats to the high lands, but built on
the ground there as they find 1t, again
trusting to their pudding skill to pre-
vent or repair any leak, as the pressure
and force of the water here is not near
so great as it is in the channel OF
tho creek, where a place is left
for 1t to flow over. So skillfully
can they stop leak that have fire.
auently seen log running through
the dam under three or four feet head
of water, and yet scarcely drop es-
Gaping, feat which every dam, builder
knows is hard to do. They use moss and
leaves at job of this kind, and push
it in almost as firmly as calker does II
vessel. So firm and substantial Is their
work done that / have known their
dams to keep full for years after the
beavers had been killed Off On one
occasion | saw dam at the head of q
stream where the supply of water in dry
weather was so small that evaporation
carried it all away, leaving the channel
below quite dry, yet the dam was so
tight that the pond was kept full. In
very high dams, built on places where
The foundation Is not very good, they
often build one. or more. smaller dams
below, so as to ease the pressure on the
main one above. They work with a
will, and without waste of labor. and
their work progresses at q surprising
rate. .tA,
Though a dam, such rs the one
above, may be several years before 1t
attains its full proportions Qor they on
ly work as their necessities requlre)
vet | have known two beavers In one
night throw q dam across a creek
which think two men could hardly do
in the same length of time. The dam
completed, they erect their houses gen.
orally on the edge of the deep channel
they have dug out in building their
dams, or on the edge of the channel OF
the creek that runs through the pond.
but if further back they always dig out
deep channels to connect their homes
with the deep water elsewhere, making
way to escape unseen should any en-
emv disturb them. Their houses are
mounds of mud and sticks, sometimes
larger, sometimes smaller. Some are
only two or three feet high. others ten
or fifteen. They are followed out in
side somewhat in the shape OF the
Lnnna .otifaidn- and the cavity of each